From Three-Photon Greenberger-Horne-Zeilinger States to Ballistic Universal Quantum Computation
Abstract
Single photons, manipulated using integrated linear optics, constitute a promising platform for universal quantum computation. A series of increasingly efficient proposals have shown linear-optical quantum computing to be formally scalable. However, existing schemes typically require extensive adaptive switching, which is experimentally challenging and noisy, thousands of photon sources per renormalized qubit, and/or large quantum memories for repeat-until-success strategies. Our work overcomes all these problems. We present a scheme to construct a cluster state universal for quantum computation, which uses no adaptive switching, no large memories, and which is at least an order of magnitude more resource efficient than previous passive schemes. Unlike previous proposals, it is constructed entirely from loss-detecting gates and offers a robustness to photon loss. Even without the use of an active loss-tolerant encoding, our scheme naturally tolerates a total loss rate ∼1.6 % in the photons detected in the gates. This scheme uses only 3 Greenberger-Horne-Zeilinger states as a resource, together with a passive linear-optical network. We fully describe and model the iterative process of cluster generation, including photon loss and gate failure. This demonstrates that building a linear-optical quantum computer needs to be less challenging than previously thought.
- Publication:
-
Physical Review Letters
- Pub Date:
- July 2015
- DOI:
- arXiv:
- arXiv:1410.3720
- Bibcode:
- 2015PhRvL.115b0502G
- Keywords:
-
- 03.67.Lx;
- 03.67.Bg;
- 42.50.Dv;
- 42.50.Ex;
- Quantum computation;
- Entanglement production and manipulation;
- Nonclassical states of the electromagnetic field including entangled photon states;
- quantum state engineering and measurements;
- Optical implementations of quantum information processing and transfer;
- Quantum Physics
- E-Print:
- Minor changes to match published version. 10 pages and 14 figures including the supplementary material